1. Technical Field
The present invention relates to an organic electroluminescence device that has an input function. The invention further relates to an electronic apparatus that is provided with such an organic electroluminescence device.
2. Related Art
Small-sized information and electronic devices such as personal digital assistants (PDA) and personal computers have become widely used in recent years. With the increasing use of these devices, display devices having a so-called touch panel function have also come into wide use. A display device having a touch panel function allows a user to manually input instructions or the like therein; specifically, a user can make an input by contacting a touching object such as a finger, a pen, or the like, onto the display screen of such a touch-panel display device. In the technical field of touch panel display devices, a capacitive sensing scheme is known as an example of a method for detecting the contact position of a touching object such as a finger or the like, which is disclosed in, for example, JP-A-2006-146895 and JP-A-2003-196023. The capacitive sensing scheme is defined as a method for detecting the contact position of, for example, a finger or the like by means of electrostatic capacitance. When a user touches on the touch-sensitive display screen of a touch panel, electrostatic capacitance is generated. A weak electric current flows as electrostatic capacitance is generated. In the capacitive sensing scheme, the contact position of a touching object is detected on the basis of the amount of such a weak electric current that flows as electrostatic capacitance is generated. A detection electrode that is formed as a sheet and a dielectric film that is deposited on the planar (i.e., sheet-type) detection electrode are used in the capacitive sensing scheme. With such a configuration, in the capacitive sensing scheme, electrostatic capacitance is generated when a user touches on the dielectric film with their finger.
A touch-sensitive liquid crystal device of the related art that conforms to the capacitive sensing scheme has a problem of a possible contact position detection error due to an electric field noise. That is, since an electric field, which is generated by a driving signal that is supplied between a pair of electrodes for driving a liquid crystal layer, undesirably reaches a detection electrode, the accuracy in the detection of a contact position decreases because of the electric field component that disturbs the functioning of the detection electrode as a noise. In order to address such a noise problem, the first-mentioned patent publication described above discloses a noise-cutting technique, which rejects a noise by means of a noise-cutting signal that is generated from a driving signal.
However, according to the configuration of the related-art liquid crystal device having a touch panel function described above, the following technical problem remains to be solved. That is, the touch-sensitive liquid crystal device of the related art described above has a technical disadvantage in that it requires a complex system for the generation of a noise-cutting signal. Therefore, there is a demand for a display device having a touch panel function that can overcome an electric field noise problem described above without involving a complex system, which is not desirable.